This invention relates to a flat knitting machine having electromechanically controlled needle selector means.
Several kinds of flat knitting machines are already known which are provided with a needle selector system controlled by electromechanical control means for the purpose of knitting as programmed in accordance with the required color design or knitting pattern. In these flat knitting machines, neddle jacks are pivotally and longitudinally movably disposed, behind the needles, in the needle tricks in which the needles are displaceably housed, and the needle jacks can be selectively moved forward or pivotally displaced or bent by the medium of electromechanically controlled needle selector means provided on the carriage; the butts of only the jacks so selected are caused to project into the operative zone of the knitting locks provided on the carriage, and thereupon the needles in front of the selected jacks are caused to knit or tuck by the action of the jacks and knitting locks acting on the butts of the jacks.
These prior art knitting machines which incorporate electromechanically controlled needle selector means for selective movement or projection of jack butts into the operative zone of the knitting locks are broadly classified into two types. One type is such that for individual jacks or for individual subjacks disposed behind the jacks in the needle tricks, there are provided, on the needle bed side, solenoids which act as needle jack selectors, and the butts of only the needle jacks selected by the solenoids are projected or displaced into the operative zone of the knitting locks. (Among the knitting machines of this type are those disclosed in West German Pat. Nos. 1635968 and 22224, Swiss Pat. No. 466487, and Japanese Pat. Publication No. 1582 of 1972.) The other type is such that selector jacks having individual selector butts thereon at individually different positions are longitudinally movably disposed in the needle tricks and behind the needle jacks and there are provided on the carriage electromechanically controlled needle selector means acting or the selector butts, whereby the selector jacks are selectively actuated to move foward so that the butts of the needle jacks thereby selected are urged to project or move forward into the operative zone of the knitting locks. (Knitting machines of this second type are dischlosed, by way of example, in West German Pat. Nos. 2010973 and 2315334, Swiss Pat. No. 460232, and Japanese Pat. Publication Nos. 30623 of 1977 and 14343 of 1977.)
The present invention relates to the improvement of a flat knitting machine having needle selector means of the latter mentioned type.
In any prior art flat knitting machine having a needle selector system of the latter type, when the selector jacks selected by the needle selector means are moved forward or displaced into an operative position, the needle jacks thereby selected (group A) are brought into the operative zone of the knitting locks on the carriage and those unselected (group B) are kept outside the operative zone of the knitting locks. In this case, the needle jacks of group A are allowed to perform knitting operation by the action of the knitting locks, but group B needle jacks can not be caused to participate in knitting operation by the action of the knitting locks without passing through further selection process.
For example, in order to knit a jacquard pattern fabric, with a prior art machine, it is necessary to carry out needle selection by electromechanical selector means on the carriage, from course to course. Upon completion of the first course knitting of face pattern, it is necessary to carry out selector jack control again, or otherwise the second course knitting of back pattern can not be performed.